Na + /H+ antiporter

Blumwald, E. Poole, R.J. (1987). Salt tolerance in suspension cultures of sugar beet. Induction of Na /H" antiport activity at the tonoplasts by growth and salt. Plant Physiology, 83, 884-7. 

Ionization may be used to counteract disregulation of pH levels (which is maintained through the concerted action of Na /H antiporters, CL/HCO3" exchangers, and other channels and/or transporters that exist within the plasma membrane of eucaryotic cells [32,100,101]). Indeed, it has been shown that iono-phores (such as nigericin [102]) can lower the intracellular pH, while weak acids (such as propionic acid) can promote acidification. Likewise, nonsteroidal anti-... 

Hunte C, Screpanti E, Venturi M, Rimon A, Padan E, Michel H (2005) Structure of a Na+/H+ antiporter and insights into mechanism of action and regulation by pH. Nature 435 1197-1202. 

Na+-glucose, Na+-amino acid, Na+-phosphate, and NaMactate sym-porter mechanisms Na+-H+ antiporter mechanism first half of the proximal tubule... 

Fluorescein-5-maleimide also has been used to study the assembly dynamics of mycobacterium tuberculosis (Chen et al., 2007), to study monomers and dimers of nhaa Na+/H+ antiporter of E. coli (Rimon et al., 2007), and to investigate the regulation of the protein disulfide proteome by mitochondria (Yang et al., 2007). 

Rimon, A., Tzubery, T., and Padan, E. (2007) Monomers of nhaa NA+/H+ antiporter of Escherichia coli are fully functional yet dimers are beneficial under extreme stress conditions at alkaline ph in the presence of NA+ or LI+. /. Biol. Chem. 10.1074/jbc.M704469200. 

Intracellular pH in brain is regulated by Na+,H+ antiporters, anion antiporters and Na+, HC03 symporters 87... 

Na+,H+ antiporters (NHE) occur in synaptosomes, glia and neuroblastoma cells [60] (Fig. 5-8B). They are relatively inactive at neutral pH but with a decrease in intracellular pH they produce an efflux of protons at the expense of the Na+ gradient. The NHE transport stoichiometry is 1 1. Activation by an internal pH decrement apparently results from protonation of a cytoplasmic site, which allosterically increases the affinity of the proton ionophoric site. In some cells, the NHE is under additional control by receptor mechanisms. Several growth factors and hormones produce transient cytoplasmic alkalinization, probably by mediating a protein kinase... 

MAPKAP MAP-kinase-activated protein kinase NHE Na+/H+ antiporter... 

This section will mainly concentrate on a few subfamilies of the major facilitator family, namely the sugar phosphate/anion antiporters, the Na+/H+ antiporters, and one example of the oxalate/formate antiporters. 

Inoue, H., Sakurai, T., Ujike, S., Tsuchiya, T., Murakami, H. and Kanazawa, H. (1999). Expression of functional Na+/H+ antiporters of Helicobacter pylori in antiporter-deficient Escherichia coli mutants, FEBS Lett., 443, 11-16. 

Pinner, E., Padan, E. and Schuldiner, S. (1992). Cloning, sequencing, and expression of the nhaB gene, encoding a Na+/H+ antiporter in Escherichia coli, J. Biol. Chem., 267, 11064-11068. 

The role of the Na+/H+ antiporter in human neutrophil NADPH-oxidase activation. J. Leuk. Biol. 43,183-6. 

The two ammonium ions produced from glutamine as illustrated in Figures 8.4 to 8.6 are secreted into the PCT lumen the by a Na+/H+ antiport (the NH4+ substitutes for H+). Subsequent metabolism of 2-oxoglutarate has the potential to generate two bicarbonate ions from the hydration of carbon dioxide by carbonic anhydrase ... 

Bicarbonate ions secreted into the blood stream help maintain the normal plasma bicarbonate concentration of approximately 25 mmol/1, whilst the two protons are secreted into the lumen of the proximal tubule in exchange for sodium via a Na+/H+ antiport. 

Rajotte D, Haddad P, Haman A, Cragoe EJJr, Hoang T (1992) Role of protein kinase C and the Na /H antiporter in suppression of apoptosis by grandocyte macrophage colony-stimulating factor and interleukin-3. J Biol Chem 267 9980-9987... 

Sano, K., Cott, G., Voelker, D., and Mason, R. (1988). The Na+/H+ antiporter in rat alveolar type II cells and its role in stimulated sufactant secretion. Biochem. Biophys. Acta, 939, 449 158. 

Nofer JR, Tepel M, Kehrel B, et al. Low-density lipoproteins inhibit the Na H antiport in human platelets. A novel mechanism enhancing platelet activity in hypercholesterolemia. Circulation 1997 95 1370-1377. 

Frelin, C., Vigne, P., Breittmayer, J.P. (1990a). Palytoxin acidifies chick cardiac cells and activates the Na+/H+ antiporter. FEBS Lett. 264,63-66. 

Sardet, C Franchi, A., Pouyssegur, J. (1989). Molecular cloning, primary structure and expression of the human growth factor activatable Na+/H+ antiporter. Cell 56,271-281. 

Schwartz, M.A., Lechene, C., Ingher, D.E. (1991). Insoluble fibronectin activates the Na/H antiporter by clustering and immobilizing integrin Ctjp, independent of cell shape. Proc. Nad. Acad. Sci. USA 88, 7849-7853. 

Sun, IX., Garcia-Canero, R., Liu, W.,Toole-Simms, W, Crane, F.L., Morrti, DX, Low, H. (1987b). Diferric transferrin stimulates the Na+/H+ antiport of HeLa cells. Biochem. Biophys. Res. Commun. 145,467 473. 

Viniegra, S., Cragoe, EJ. Jr., Rabito, C.A. (1992). Heterogeneity of the Na+/H+ antiport systems in renal cells. Biochim. Biophys. Acta 1106,99-109. 

Zhao, Z. Willis, J.S. (1993). Cold activation of Na influx through the Na+/H+ antiport of guinea pig red cells. J. Memb. Biol. 131,43-54. 

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